The present invention is in the field of hard surface cleaning compositions, in particular it relates to products and methods suitable for the removal of cooked-, baked- and burnt-on soils from cookware and tableware.
Cooked-, baked- and burnt-on soils are amongst the most severe types of soils to remove from surfaces. Traditionally, the removal of cooked-, baked- and burnt-on soils from cookware and tableware requires soaking the soiled object prior to a mechanical action. Apparently, the automatic dishwashing process alone does not provide a satisfactory removal of cooked-, baked- and burnt-on soils. Manual dishwashing process requires a tremendous rubbing effort to remove cooked-, baked- and burnt-on soils and this can be detrimental to the safety and condition of the cookware/tableware.
The use of cleaning compositions containing solvent for helping in the removal of cooked-, baked- and burnt-on solids is known in the art. For example, U.S. Pat. No. 5,102,573 provides a method for treating hard surfaces soiled with cooked-on, baked-on or dried-on food residues comprising applying a pre-spotting composition to the soiled article. The composition applied comprises surfactant, builder, amine and solvent. U.S. Pat. No. 5,929,007 provides an aqueous hard surface cleaning composition for removing hardened dried or baked-on grease soil deposits. The composition comprises nonionic surfactant, chelating agent, caustic, a glycol ether solvent system, organic amine and anti-redeposition agents. WO-A-94/28108 discloses an aqueous cleaner concentrate composition, that can be diluted to form a more viscous use solution comprising an effective thickening amount of a rod micelle thickener composition, lower alkyl glycol ether solvent and hardness sequestering agent. The application also describes a method of cleaning a food preparation unit having at least one substantially vertical surface having a baked food soil coating. In practice, however, none of the art has been found to be very effective in removing baked-on, polymerized soil from metal and other substrates.
Thus, there is still need for cleaning compositions and methods used prior to the washing process of tableware and cookware soiled with cooked-on, baked-on or burnt-on food in order to facilitate the removal of these difficult food residues. Compositions effective for the removal of cooked-, baked- or burnt-on soils generally contain chemicals which have an unpleasant odor associated with them. Normally said malodorous base odour is masked using a perfume. However when using the solvents of the present invention the malodour is so strong that normal levels of perfume do not adequately mask the malodour. One solution to this problem is to use higher levels of perfume, however then the perfume is overbearing and equally unpleasant to the user. Another method used in the art is to mask the odour using a perfume comprising particularly strong smelling elements, but which are not perceived by the consumer as overbearing for example essential oils or herbal notes. It has therefore been the object of the present invention to provide a composition suitable for the removal of cooked-, baked- or burnt-on soils with minimum malodor and pleasant odor during use in order to provide a more enjoyable cleaning experience for the user.
The problems discussed above can be exacerbated in spray-type compositions and products. Furthermore, in the case of compositions for the removal of cooked-, baked- or burnt-on soils the contact of these compositions with the soils can aggravate the malodor issue. Another factor which can aggravate the malodor issue is the interaction of the cleaning composition with water leading to a perceived malodor, for instance, when the user rinses off the composition from the treated utensil. Accordingly, it is another object of the present invention to provide sprayable household cleaning compositions with minimum malodor and pleasant odor during use in order to provide a more enjoyable cleaning experience for the user.
According to a first aspect of the present invention, there is provided a hard surface cleaning composition for removing cooked-, baked- or burnt-on soils (such as grease, meat, dairy, fruit, pasta and any other food especially difficult to remove after the cooking process) from cookware and tableware (including stainless steel, glass, plastic, wood and ceramic objects), wherein the composition has surface tension of less than 30 mN/m and comprises an organic solvent system and no more than:
0.09% by weight of the composition of ethers having molecular weight of less than 210
0.007% by weight of the composition of esters having molecular weight of less than 110
0.045% by weight of the composition of glycol ethers having molecular weight of less than 130
0.0025% by weight of the composition of ketones having molecular weight of less than 90.
The composition is preferably in sprayable form and incorporated in a spray dispenser. The spray droplet size is also preferably carefully controlled by the inclusion of a thickening system as herein described.
The present composition comprises an organic solvent system. A problem generally associated with the use of organic solvents in cleaning compositions is that of solvent odorxe2x80x94an odor which many consumers do not like and which they perceive as xe2x80x9cmalodorousxe2x80x9d. Such compositions can be made more attractive to consumers by using a high concentration of perfumes. The addition of such high concentrations of perfumes can alter or reduce the overall offensive character of the compositions, but it often results in an undesirably overbearing perfume odor. Moreover, these malodor problems can be exacerbated in compositions designed for spray-type applications. The Applicants according to the present invention have dealt with this problem via a different and previously unexplored route. The Applicants rather than attempting to mask the odour have sought to eliminate it or at least reduce it to a point where normal levels of perfume can be used to mask the malodour.
The Applicants have found that by eliminating or reducing the level of certain chemicals from the composition the existence of malodour can be dramatically reduced. These particularly malodorous chemicals are removed by fractional distillation using known techniques.
Hence the composition of the present invention, whilst comprising a solvent system, comprises no more than 0.09% by weight of the composition of ethers having molecular weight of less than 210; 0.007% by weight of the composition of esters having molecular weight of less than 1 10; 0.045% by weight of the composition of glycol ethers having molecular weight of less than 130; and 0.0025% by weight of the composition of ketones having molecular weight of less than 90. More preferably the composition comprises no more than 0.045% by weight of the composition of ethers having molecular weight of less than 210; 0.0035% by weight of the composition of esters having molecular weight of less than 110;
0.0225% by weight of the composition of glycol ethers having molecular weight of less than 130; and
0.00125% by weight of the composition of ketones having molecular weight of less than 90.
Such solvents are available from Dow under the tradename of low odour Dowanal PnB.
Examples of chemicals which should be limited, preferably excluded from the composition include: butyl formate (MW 102), 1-(propoxy) butane (MW1 16), 1-(2-propenyloxy)-butane (MW 114), n-butyl ether (MW130), 1-(1-methylpropoxy)-butane (MW131), diisopropyl ether (MW104), dibutoxy butane (MW203), 1-(1-dibutoxy)-butane (MW202), 1-(2-propenyloxy)-2 propanol (MW116), 1-(2-methylpropoxyl)-2-propanol (MW133), 1-butoxy-2-propanol (MW133), 1-(1-methylethoxy)-propanol (MW 119), 2-heptanone (85), and mixtures thereof.
The compositions of the present invention have a surface tension of less than 30 mN/m. More preferably the composition has a surface tension of less than 28 mN/m, more preferably less than 26 mN/m, even more preferably less than about 24 mN/m and most preferably less than 23.5 mN/m. Said surface tension is provided by the solvent system, but may also be supplemented by the presence of surfactants.
Preferably the solvent system comprises a soil swelling and spreading multi-functionality. Also highly preferred from the viewpoint of optimum removal of baked-on polymerised soils are compositions comprising a solvent having a limited miscibility in water (herein referred to as a coupling solvent) preferably in combination with a fully-miscible solvent, both preferably at specific levels in composition. Thus in another preferred embodiment, the composition herein comprises from about 10% to about 40%, preferably from about 12% to about 20% of solvent system. More preferably said solvent system comprises from about 1% to about 15% of solvent acting as soil swelling agent and from about 7% to about 30% of solvent acting as spreading auxiliary. Said spreading auxiliary preferably includes at least about 3.5% of a water-miscible solvent and at least about 3.5% of a coupling solvent having limited miscibility in hg.
The soil swelling agent is present in the compositions herein in effective amounts, i.e., in amounts effective to provide the necessary soil swelling functionality. A soil swelling agent is understood herein to be a substance or composition capable of swelling cooked-, baked- or burnt-on soil deposited on a substrate after treating said substrate with the soil swelling agent without the application of external mechanical forces. Soil swelling effect can be quantified by the soil swelling index.
The soil swelling index (SSI) is a measure of the increased thickness of soil after treatment with a substance or composition in comparison to the soil before treatment with the substance or composition. It is believed, while not being limited by theory, that the thickening is caused, at least in part, by hydration or solvation of the soil. Swelling of the soil makes the soil easier to remove with no or minimal application of force, e.g. wiping, rinsing or manual and automatic dishwashing. The measuring of this change of soil thickness gives the SSI.
The amount of substance or composition necessary to provide soil swelling functionality will depend upon the nature of the substance or composition and can be determined by routine experimentation. Other conditions effective for soil swelling such as pH, temperature and treatment time can also be determined by routine experimentation. Preferred herein, however are substances and compositions effective in swelling cooked-, baked- or burnt-on soils such as polymerised grease or carbohydrate soils on glass or metal substrates, whereby after the substance or composition has been in contact with the soil for 45 minutes or less, preferably 30 min or less and more preferably 20 min or less at 20xc2x0 C., the substance or composition has an SSI at 5% aqueous solution and pH of 12.8 of at least about 15%, preferably at least about 20% more preferably at least about 30% and especially at least about 50%. Preferably also the choice of soil swelling agent is such that the final compositions have an SSI measured as neat liquids under the same treatment time and temperature conditions of at least about 100%, preferably at least about 200% and more preferably at least about 500%. Highly preferred soil swelling agents and final compositions herein meet the SSI requirements on polymerized grease soils according to the procedure set out below.
SSI is determined herein by optical profilometry, using, for example, a Zygo NewView 5030 Scanning White Light Interferometer. A sample of polymerized grease on a brushed, stainless steel coupon is prepared as described hereinbelow with regard to the measurement of polymerized grease removal index. Optical profilometry is then run on a small droplet of approximately 10 xcexcm thickness of the grease at the edge of the grease sample. The thickness of the soil droplet before (Si) and after (Sf) treatment is measured by image acquisition by means of scanning white light interferometry. The interferometer (Zygo NewView 5030 with 20X Mirau objective) splits incoming light into a beam that goes to an internal reference surface and a beam that goes to the sample. After reflection, the beams recombine inside the interferometer, undergo constructive and destructive interference, and produce a light and dark fringe pattern. The data are recorded using a CCD (charged coupled device) camera and processed by the software of the interferometer using Frequency Domain Analysis. The dimensions of the image obtained (in pixels) is then converted in real dimension (xcexcm or mm). After the thickness of the soil (Si) on the coupon has been measured the coupon is soaked in the invention composition at ambient temperature for a given length of time and the thickness of the soil (Sf) is measured repeating the procedure set out above. If necessary, the procedure is replicated over a sufficient member of droplets and samples to provide statistical significance.
The SSI is calculated in the following manner:
SSI=[(Sfxe2x88x92Si)/Si]xc3x97100
The compositions herein preferably also include a spreading auxiliary. The function of the spreading auxiliary is to reduce the interfacial tension between the soil swelling agent and soil, thereby increasing the wettability of soils by the soil swelling agents. The spreading auxiliary when added to the compositions herein containing soil swelling agents leads to a lowering in the surface tension of the compositions, preferred spreading auxiliaries being those which lower the surface tension below that of the auxiliary itself. Especially useful are spreading auxiliaries able to render a surface tension below about 26 mN/m, preferably below about 24.5 mN/m and more preferably below about 24 mN/m, and especially below about 23.5 mN/m and a pH, as measured in a 10% solution in distilled water, of at least 10.5. Surface tensions are measured herein at 25xc2x0 C.
Without wishing to be bound by the theory, it is believed that the soil swelling agent penetrates and hydrates the soils. The spreading auxiliary facilitates the interfacial process between the soil swelling agent and the soil and aids swelling of the soil. The soil penetration and swelling is believed to weaken the binding forces between soil and substrate. The resulting compositions are particularly effective in removing soils of a polymerized baked-on nature from metallic substrates.
Suitable soil swelling agents for use herein can be selected from organoamine solvents inclusive of alkanolamines, alkylamines, alkyleneamines and mixtures thereof.
Spreading auxiliaries for use herein can be selected generally from organic solvents, including fully miscible solvents and coupling solvents with limited miscibility, wetting agents and mixtures thereof. In preferred embodiments the liquid surface tension of the spreading auxiliary is less than about 30 mN/m, preferably less than about 28 mN/m, more preferably less than about 26 mN/m and more preferably less than about 24.5 mN/m. Suitable organic solvents capable of acting as spreading auxiliaries include alcoholic solvents, glycols and glycol derivatives and mixtures thereof. Preferred for use herein are mixtures of diethylene glycol monobutyl ether and propylene glycol butyl ether.
A preferred spreading auxiliary herein comprises a mixture of a fully water-miscible organic solvent and a coupling organic solvent having limited miscibility in water and wherein the ratio of water-miscible organic solvent to coupling organic solvent is in the range from about 4:1 to about 1:20, preferably from about 2:1 to about 1:6, more preferably from about 1.5:1 to about 1:3. A water-miscible solvent herein is a solvent which is miscible with water in all proportions at 25xc2x0 C. A coupling solvent with limited miscibility is a solvent with is miscible with water in some but not all proportions at 25xc2x0 C. Preferably the limited miscibility solvent has a solubility in water at 25xc2x0 C. of less than about 30 wt %, more preferably less than about 20 wt %. Preferably also the solubility of water in the limited miscibility solvent at 25xc2x0 C. is less than about 30 wt %, more preferably less than about 20 wt %.
Other suitable spreading auxiliaries comprise a wetting agent having a liquid surface tension of less than about 30 mN/m, preferably less than about 28 mN/m, more preferably less than about 26 mN/m and more preferably less than 24.5 mN/m. Wetting agents suitable for use as spreading auxiliaries herein are surfactants and include anionic, amphoteric, zwitterionic, nonionic and semi-polar surfactants. Preferred nonionic surfactants include silicone surfactants, such as Silwet copolymers, preferred Silwet copolymers include Silwet L-8610, Silwet L-8600, Silwet L-77, Silwet L-7657, Silwet L-7650, Silwet L-7607, Silwet L-7604, Silwet L-7600, Silwet L-7280 and mixtures thereof. Preferred for use herein is Silwet L-77.
Other suitable wetting agents include organo amine surfactants, for example amine oxide surfactants. Preferably, the amine oxide contains an average of from 12 to 18 carbon atoms in the alkyl moiety, highly preferred herein being dodecyl dimethyl amine oxide, tetradecyl dimethyl amine oxide, hexadecyl dimethyl amine oxide and mixtures thereof.
Suitable spreading auxiliaries for use herein include surfactants (especially those having a surface tension of less than about 25 mN/m) such as silicone surfactants and amine oxide surfactants, organic solvents and mixtures thereof. Preferably the wetting agent is an amine oxide. Highly preferred spreading auxiliaries comprise a mixture of the coupling solvent and the wetting agent.
In preferred embodiments the hard surface cleaning compositions comprise an organic solvent system including at least one solvent component acting as soil swelling agent and wherein the organic solvent system is selected from alcohols, amines, esters, glycol ethers, glycols, terpenes and mixtures thereof. Suitable organic solvents can be selected from organoamine solvents, inclusive of alkanolamines, alkylamines, alkyleneamines and mixtures thereof; alcoholic solvents inclusive of aromatic, aliphatic (preferably C4-C10) and cycloaliphatic alcohols and mixtures thereof; glycols and glycol derivatives inclusive of C2-C3 (poly)alkylene glycols, glycol ethers, glycol esters and mixtures thereof; and mixtures selected from organoamine solvents, alcoholic solvents, glycols and glycol derivatives. Highly preferred organoamine solvents include 2-aminoalkanol solvents as disclosed in U.S. Pat. No. 5,540,846.
In preferred compositions of the present invention the organic solvent comprises organoamine (especially alkanolamine) solvent and glycol ether solvent, preferably in a weight ratio of from about 3:1 to about 1:3. Where present the glycol ether solvent is preferably selected from ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monobutyl ether, dipropylene glycol monobutyl ether, ethylene glycol phenyl ether and mixtures thereof. Preferred organoamine for use herein are alkanolamines, especially monoethanol amine, methyl amine ethanol and 2-amino-2methyl-propanol. In a preferred composition the glycol ether is a mixture of diethylene glycol monobutyl ether and propylene glycol butyl ether, preferably in a weight ratio of from about 1:2 to about 2:1.
Solvents that can be used herein include: i) alcohols, such as benzyl alcohol, 1,4-cyclohexanedimethanol, 2-ethyl-1-hexanol, furfuryl alcohol, 1,2-hexanediol and other similar materials; ii) amines, such as alkanolamines (e.g. primary alkanolamines: monoethanolamine, monoisopropanolamine, diethylethanolamine, ethyl diethanolamine, beta-aminoalkanols; secondary alkanolamines: diethanolamine, diisopropanolamine, 2-(methylamino)ethanol; ternary alkanolamines: triethanolamine, triisopropanolamine); alkylamines (e.g. primary alkylamines: monomethylamine, monoethylamine, monopropylamine, monobutylamine, monopentylamine, cyclohexylamine), secondary alkylamines: (dimethylamine), alkylene amines (primary alkylene amines: ethylenediamine, propylenediamine) and other similar materials; iii) esters, such as ethyl lactate, methyl ester, ethyl acetoacetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate and other similar materials; iv) glycol ethers, such as ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol butyl ether and other similar materials; v) glycols, such as propylene glycol, diethylene glycol, hexylene glycol (2-methyl-2,4 pentanediol), triethylene glycol, composition and dipropylene glycol and other similar materials; and mixtures thereof.
Preferred solvents to be used herein as soil swelling agents comprise alkanolamines, especially monoethanolamine, beta-aminoalkanols, especially 2-amine-2methyl-propanol (since it has the lowest molecular weight of any beta-aminoalkanol which has the amine group attached to a tertiary carbon, therefore minimize the reactivity of the amine group) and mixtures thereof.
Preferred solvents for use herein as spreading auxiliaries comprise glycols and glycol ethers, especially diethylene glycol monobutyl ether, propylene glycol butyl ether and mixtures thereof.
In general terms, solvents for use herein should be selected so as to be compatible with the tableware/cookware as well as with the different parts of an automatic dishwashing machine. Furthermore, the solvent system should be effective and safe to use having a volatile organic content above 1 mm Hg (and preferably above 0.1 mm Hg) of less than about 50%, preferably less than about 30%, more preferably less than about 10% by weight of the solvent system. Also they should have very mild pleasant odors. The individual organic solvents used herein generally have a boiling point above about 150xc2x0 C., flash point above about 50xc2x0 C., preferably below 100xc2x0 C. and vapor pressure below about 1 mm Hg, preferably below 0.1 mm Hg at 25xc2x0 C. and atmospheric pressure. In addition, the individual organic solvents preferably have a molar volume of less than about 500, preferably less than about 250, more preferably less than about 200 cm3/mol, these molar volumes being preferred from the viewpoint of providing optimum soil penetration and swelling.
A preferred solvent system for use herein has a volatile organic content above 1 mm Hg of less than about 50%, preferably less than about 20%, more preferably less than about 10%. Preferably, the organic solvent is essentially free of solvent components having a boiling point below about 150xc2x0 C., flash point below about 50xc2x0 C., preferably below 100xc2x0 C. or vapor pressure above about 1 mm Hg. A highly preferred organic solvent system has a volatile organic content above 0.1 mm Hg of less than about 50%, preferably less than about 20%, more preferably less than about 10% and even more preferably less than about 4%.
In terms of solvent parameters, the organic solvent can be selected from:
a) polar, hydrogen-bonding solvents having a Hansen solubility parameter of at least 20 (Mpa)1/2, a polarity parameter of at least 7 (Mpa)1/2, preferably at least 12 (Mpa)1/2 and a hydrogen bonding parameter of at least 10 (Mpa)1/2
b) polar non-hydrogen bonding solvents having a Hansen solubility parameter of at least 20 (Mpa)1/2, a polarity parameter of at least 7 (Mpa)1/2, preferably at least 12 (Mpa)1/2 and a hydrogen bonding parameter of less than 10 (Mpa)1/2
c) amphiphilic solvents having a Hansen solubility parameter below 20 (Mpa)1/2, a polarity parameter of at least 7 (Mpa)1/2 and a hydrogen bonding parameter of at least 10 (Mpa)1/2
d) non-polar solvents having a polarity parameter below 7 (Mpa)1/2 and a hydrogen bonding parameter below 10 (Mpa)1/2 and
e) mixtures thereof.
Thus, in another preferred embodiment the composition herein comprises a soil swelling agent, a coupling solvent having limited miscibility in water and a wetting agent and wherein the composition has a liquid surface tension of less than about 26 mN/m and preferably less than about 24.5 mN/m.
The compositions herein are further characterised by displaying surface tension lowering characteristics, which is believed is important for ensuring optimum soil removal performance on polymerised soils. Thus, in another preferred embodiment, the composition herein comprises an solvent system and a wetting agent, wherein the solvent system includes at least one solvent component acting as soil swelling agent and wherein the wetting agent is effective in lowering the surface tension of the solvent system to at least 1 mN/m less than that of the wetting agent.
Thus in a preferred embodiment, the composition herein comprises a polymerised grease swelling agent and a spreading auxiliary and has a liquid surface tension of less than about 26 mN/m, preferably less than about 24.5 mN/m and more preferably less than about 24 mN/m and a pH, as measured in a 10% solution in distilled water, of at least 10.5.
The compositions of the invention are also particularly effective in removing baked-on carbohydrate based soils from cookware/tableware, apparently by a mechanism including swelling and rehydration of the soils. Thus, in another embodiment, the composition herein comprises a carbohydrate soil swelling and agent and a spreading auxiliary and has a liquid surface tension of less than about 26 mN/m, preferably less than about 24.5 mN/m and more preferably less than about 24 mN/m and a pH, as measured in a 10% solution in distilled water, of at least 10.5.
Preferred carbohydrate swelling agents herein act as rehydrating agents and are able to decrease the area under the curve of the absorbance of carbohydrate Cxe2x80x94O infra-red band (spanning a wavelenth of from about 900 cmxe2x88x921 to about 1200 cmxe2x88x921 with major peaks at about 1016 cmxe2x88x921 and about 1145 cmxe2x88x921) by at least about 5% and preferably at least about 10%, after said re-hydrating agent has been in contact with the soil for less than about 30 min, preferably less than about 20 min. Again the rehydrating agent is applied in the form of an aqueous solution or dispersion and the level effective for rehydration is determined by routine experimentation.
The compositions herein are characterized by extremely low liquid surface tensions and contact angles on polymerized grease-coated substrates. In preferred embodiments of the invention the soil swelling agent and spreading auxiliary are selected such that the hard surface cleaning composition displays an advancing contact angle on a polymerised grease-coated glass substrate at 25xc2x0 C. of less than about 20xc2x0, preferably less than about 10xc2x0 and more preferably less than about 5xc2x0.
The method for determining contact angle is as follows. A sample plate (prepared as described below) is dipped into and pulled out of a liquid and contact angles calculated after Wilhelmy Method. The force exerted on the sample according to the immersion depth is measured (using a Kruss K12 tensiometer and System K121 software) and is proportional to the contact angle of the liquid on the solid surface. The sample plate is prepared as follows: Spray 30-50 grams of Canola Oil into a beaker. Dip a glass slide (3xc3x979xc3x970.1 cm) into the Oil and thoroughly coat the surface. This results in an evenly dispersed layer of oil on the surface. Adjust the weight of product on the slide""s surface until approximately 0.5 g of oil has been delivered and evenly distributed. At this point, bake the slides at 245xc2x0 C. for 20 minutes, and allow to cool to room temperature.
Thus, in another preferred embodiment, the composition herein comprises a soil swelling agent and a spreading auxiliary and displays an advancing contact angle (as measured by the method described herein above) on a polymerised grease-coated glass substrate at 25xc2x0 C. of less than about 20xc2x0, preferably less than about 100 and more preferably less than about 5xc2x0.
The compositions of the invention are characterized by excellent performance on polymerized grease and preferably the compositions of the present invention have a polymerised grease removal index of at least 25%, preferably at least 50%, more preferably at least 75%. Polymerized grease removal index is a measure of how much soil is removed from a surface after treatment with the composition of the invention. The soiled substrates are soaked in the invention composition at ambient temperature for about 45 min or less, preferably for about 30 min or less and more preferably for about 20 min or less and then washed in a dishwasher without detergent or rinsing agent. The substrates are then dried and weighed and the soil removal is determined by gravimetric analysis. The soiled substrates are prepared as follows: Stainless steel coupons/slides are thoroughly cleaned with the product of the invention and rinsed well with water. The slides are placed in a 50xc2x0 C. room to facilitate drying, if needed. The coupons/slides are allowed to cool to room temperature (about half an hour). The coupons/slides are weighed. Canola Oil, is sprayed into a small beaker or tri-pour (100 mL beaker, 20-30 mL of Canola Oil). A one inch paint brush is dipped into the Canola Oil. The soaked brush is then rotated and pressed lightly against the side of the container 4-6 times for each side of the brush to remove excess Canola Oil. A thin layer of Canola Oil is painted onto the surface of the coupon/slide. Each slide is then stroked gently with a dry brush in order to ensure that only a thin coating of Canola Oil is applied (two even strokes should sufficiently remove excess). In this manner 0.1-0.2 g of soil will be applied to the coupon/slide. The coupons/slides are arranged on a perfectly level cookie sheet or oven rack and placed in a preheated oven at 245xc2x0 C. The slides/coupons are baked for 20 minutes. Coupons/slides are allowed to cool to room temperature (45 minutes). The cool coupons/slides are then weighed.
It is a feature of the solvent-based compositions of the invention that they display excellent performance in direct application to soiled cookware and tableware. The organic solvent system includes at least one solvent component acting as soil swelling agent and desirably has a liquid surface tension of less than about 27 mN/m, preferably less than about 26 mN/m, more preferably less than about 25 mN/m. Furthermore, the organic solvent system preferably comprises a plurality of solvent components in levels such that the solvent system has an advancing contact angle on polymerised grease-coated glass substrate of less than that of corresponding compositions containing the individual components of the solvent system. Such solvent systems and compositions are formed to be optimum for the removal of baked-on soils having a high carbon content from cookware and tableware. The compositions are preferably in the form of a liquid or gel having a pH of greater than about 9, preferably greater than 10.5 and preferably greater than about 11 as measured at 25xc2x0 C.
Optional Ingredients
Apart from the soil swelling and spreading auxiliary agent the hard surface cleaning compositions herein can comprise additional components inclusive of surfactants other that the wetting agents hereinbefore described, builders, enzymes, bleaching agents, alkalinity sources, thickeners, stabilising components, perfumes, abrasives, etc. The compositions can also comprise organic solvents having a carrier or diluent function (as opposed to soil swelling or spreading) or some other specialised function. The compositions can be dispensed from any suitable device, such as bottles (pump assisted bottles, squeeze bottles), paste dispensers, capsules, pouches and multi-compartment pouches.
pH
The composition of the invention preferably has a pH, as measured in a 10% solution in distilled water, from at least about 10.5, preferably from about 11 to about 14 and more preferably from about 11.5 to about 13.5. In the case of cleaning of cooked-, baked- or burnt-on soils cleaning performance is related in part to the high pH of the cleaning composition. However, due to the acidic nature of some of the soils, such as for example cooking oil, a reserve of alkalinity is desirable in order to maintain a high pH. On the other hand the reserve alkalinity should not be so high as to risk damaging the skin of the user. Therefore, the compositions of the invention preferably have a reserve alkalinity of less than about 5, more preferably less than about 4 and especially less than about 3. xe2x80x9cReserve alkalinityxe2x80x9d, as used herein refers to, the ability of a composition to maintain an alkali pH in the presence of acid. This is relative to the ability of a composition to have sufficient alkali in reserve to deal with any added acid while maintaining pH. More specifically, it is defined as the grams of NaOH per 100 cc""s, exceeding pH 9.5, in product. The reserve alkalinity for a solution is determined in the following manner.
A Mettler DL77 automatic titrator with a Mettler DG115-SC glass pH electrode is calibrated using pH 4, 7 and 10 buffers (or buffers spanning the expected pH range). A 1% solution of the composition to be tested is prepared in distilled water. The weight of the sample is noted. The pH of the 1% solution is measured and the solution is titrated down to pH 9.5 using a solution of 0.25N HCL. The reserve alkalinity (RA) is calculated in the following way:
RA=% NaOHxc3x97Specific gravity
xe2x80x83% NaOH=ml HClxc3x97Normality of HClxc3x9740xc3x97100/Weight of sample aliquot titrated(g)xc3x971000
Rheology Modifiers
The compositions of the invention preferably meet certain Theological and other performance parameter including both the ability to be sprayed and the ability to cling to surfaces. For example, it is desirable that the product sprayed on a vertical stainless steel surface has a flow velocity less than about 1 cm/s, preferably less than about 0.1 cm/s. For this purpose, the product is in the form of a shear thinning fluid having a shear index n (Herschel-Bulkey model) of from about 0 to about 0.8, preferably from about 0.3 to about 0.7, more preferably from about 0.4 to about 0.6. Highly preferred are shear thinning liquids having a shear index of 0.5 or lower. The fluid consistency index, on the other hand, can vary from about 0.1 to about 50 Pa.sn, but is preferably less than about 1 Pa.sn. More preferably, the fluid consistency index is from about 0.20 to about 0.15 Pa.sn. The product preferably has a viscosity from about 0.1 to about 200 Pa s, preferably from about 0.3 to about 20 Pa s as measured with a Brookfield cylinder viscometer (model LVDII) using 10 ml sample, a spindle S-31 and a speed of 3 rpm. Specially useful for use herein are compositions having a viscosity greater than about 1 Pa s, preferably from about 2 Pa s to about 4 Pa s at 6 rpm, lower than about 2 Pa s, preferably from about 0.8 Pa s to about 1.2 Pa s at 30 rpm and lower than about 1 Pa s, preferably from about 0.3 Pa s to about 0.5 Pa s at 60 rpm. Rheology is measured under ambient temperature conditions (25xc2x0 C.).
Suitable thickening agents for use herein include viscoelastic, thixotropic thickening agents at levels of from about 0.1% to about 10%, preferably from about 0.25% to about 5%, most preferably from about 0.5% to about 3% by weight. Suitable thickening agents include polymers with a molecular weight from about 500,000 to about 10,000,000, more preferably from about 750,000 to about 4,000,000. The preferred cross-linked polycarboxylate polymer is preferably a carboxyvinyl polymer. Such compounds are disclosed in U.S. Pat. No. 2,798,053, issued on Jul. 2, 1957, to Brown. Methods for making carboxyvinyl polymers are also disclosed in Brown. Carboxyvinyl polymers are substantially insoluble in liquid, volatile organic hydrocarbons and are dimensionally stable on exposure to air.
Other suitable thickening agents include inorganic clays (e.g. laponites, aluminium silicate, bentonite, fumed silica). The preferred clay thickening agent can be either naturally occurring or synthetic. Preferred synthetic clays include the synthetic smectite-type clay sold under the trademark Laponite by Southern Clay Products, Inc. Particularly useful are gel forming grades such as Laponite RD and sol forming grades such as Laponite RDS. Natural occurring clays include some smectite and attapulgite clays. Mixtures of clays and polymeric thickeners are also suitable for use herein. Preferred for use herein are synthetic smectite-type clays such as Laponite and other synthetic clays having an average platelet size maximum dimension of less than about 100 nm. Laponite has a layer structure which in dispersion in water, is in the form of disc-shaped crystals of about 1 nm thick and about 25 nm diameter. Small platelet size is valuable herein for providing a good sprayability, stability, rheology and cling properties as well as desirable aesthetic.
Other types of thickeners which can be used in this composition include natural gums, such as xanthan gum, locust bean gum, guar gum, and the like. The cellulosic type thickeners: hydroxyethyl and hydroxymethyl cellulose (ETHOCEL and METHOCEL(copyright) available from Dow Chemical) can also be used. Natural gums seem to influence the size of the droplets when the composition is being sprayed. It has been found that droplets having an average equivalent geometric diameter from about 3 xcexcm to about 10 xcexcm, preferably from about 4 xcexcm to about 7 xcexcm, as measured using a TSI Aerosizer, help in odor reduction. Preferred natural gum for use herein is xanthan gum.
Highly preferred herein from the viewpoint of sprayability, cling, stability, and soil penetration performance is a mixture of Laponite and xanthan gum. Additionally, Laponite/xanthan gum mixtures help the aesthetics of the product and at the same time control the spray droplet size and reduce the solvent odor.
Perfumes
In a preferred aspect of the present invention the composition comprises a perfume, preferably an odor masking base.
Odor-masking Base
The odor masking base (which term includes fully-formulated odor-masking perfumes or a base composition for use therein) is preferably a mixture of ionones, musks and highly volatile perfumes. Concentrations of the odor masking base preferably range from about 0.001% to about 3%, more preferably from about 0.006% to about 2.5%, even more preferably from about 0.0075% to about 1%, by weight of the composition.
The ionones, musks and highly volatile perfumes of the odor masking base are characterized in part by their respective boiling point ranges. The ionones and musks preferably have a boiling point at 1 atmosphere of pressure of more than about 250xc2x0 C., whereas the highly volatile perfume components have a boiling point at 1 atmosphere of pressure of less than about 250xc2x0 C. The boiling point of many perfume materials are disclosed in, e.g., xe2x80x9cPerfume and Flavor Chemicals (Aroma Chemicals),xe2x80x9d S. Arctander, published by the author, 1969. Other boiling point values can be obtained from different chemistry handbooks and databases, such as the Beilstein Handbook, Lange""s Handbook of Chemistry, and the CRC Handbook of Chemistry and Physics. When a boiling point is given only at a different pressure, usually lower pressure than the normal pressure of one atmosphere, the boiling point at normal or ambient pressure can be approximately estimated by using boiling point-pressure nomographs, such as those given in xe2x80x9cThe Chemist""s Companion,xe2x80x9d A. J. Gordon and R. A. Ford, John Wiley and Sons Publishers, 1972, pp. 30-36. When applicable, the boiling point values can also be calculated by computer programs, based on molecular structural data, such as those described in xe2x80x9cComputer-Assisted Prediction of Normal Boiling Points of Pyrans and Pyrroles,xe2x80x9d D. T. Stanton et al, J. Chem. Inf. Comput. Sci., 32 (1992), pp. 306-316, xe2x80x9cComputer-Assisted Prediction of Normal Boiling Points of Furans, Tetrahydrofurans, and Thiophenes,xe2x80x9d D. T. Stanton et al, J. Chem. Inf. Comput. Sci., 31 (1992), pp. 301-310, and references cited therein, and xe2x80x9cPredicting Physical Properties from Molecular Structure,xe2x80x9d R. Murugan et al, Chemtech, June 1994, pp. 17-23.
Each of the ionone perfumes, highly volatile perfumes, and musk components of the odor masking base are described in detail hereinafter.
Highly Volatile Perfume
The highly volatile perfume of the odor masking base comprises perfume materials which compete with the malodorous solvents to bind to the nasal receptor sites. These highly volatile perfumes are the first odors recognized and identified by the brain, and help inhibit or mask the olfactory recognition of the solvents. Concentrations of the highly volatile perfume range from about 15% to about 85%, preferably from about 20% to about 80%, more preferably from about 35% to about 75%, even more preferably from about 45% to about 65%, by weight of the odor masking base.
The highly volatile perfumes are more volatile than the ionone and musk components of the odor masking base, and have a boiling point of less than about 250xc2x0 C., preferably less than about 230xc2x0 C., more preferably less than about 220xc2x0 C. at 1 atmosphere of pressure. These highly volatile perfumes are classified as either aldehydes having from about 2 to about 15 carbon atoms, esters having from about 3 to about 15 carbon atoms, alcohols having from about 4 to about 12 carbon atoms, ethers having from about 4 to about 13 carbon atoms, ketones having from about 3 to about 12 carbon atoms, or combinations thereof.
Nonlimiting examples of suitable aldehydes include n-decyl aldehyde, 10-undecen-1-al, dodecanal, 3,7-dimethyl-7-hydroxyoctan-1-al, 2,4-dimethyl-3-cyclohexene carboxaldehyde, benzaldehyde, anisic aldehyde, and mixtures thereof.
Nonlimiting examples of suitable esters include ethyl acetate, cis-3-hexenyl acetate, 2,6-dimethyl-2,6-octadien-8-yl acetate, benzyl acetate, 1,1-dimethyl-2-phenyl acetate, 2-pentyloxy allyl ester, allyl hexanoate, methyl-2-aminobenzoate, and mixtures thereof.
Nonlimiting examples of suitable alcohols include n-octyl alcohol, beta-gamma-hexenol, 2-trans-6-cis-nonadien-1-ol, 3,7-dimethyl-trans-2,6-octadien-1-ol, 3,7-dimethyl-6-octen-1-ol, 3,7-dimethyl-1,6-octadien-3-ol, 2,6-dimethyl-7-octen-2-ol, 2-phenylethyl alcohol, 2-cis-3,7-dimethyl-2,6-octadien-1-ol, 1-methyl-4-iso-propyl-1-cyclohexen-8-ol, and mixtures thereof.
Nonlimiting examples of suitable ethers include amyl cresol oxide, 4-ethoxy-1-methyl-benzol, 4-methoxy-1-methyl benzene, methyl phenylethyl ether, and mixtures thereof.
Nonlimiting examples of suitable ketones include dimethyl acetophenone, ethyl-n-amyl ketone, 2-heptanone, 2-octanone, 3-methyl-2-(cis-2-penten-1-yl)-2-cyclopenten-1-one, 1-1-methyl-4-iso-propenyl-6-cyclohexen-2-one, para-tertiary-amyl cyclohexanone, and mixtures thereof.
Preferred highly volatile perfumes include 2-pentyloxy allyl ester sold under the tradename Allyl Amyl Glycolate (available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A.); benzaldehyde sold under the tradename Amandol (available from Rhone-Poulenc, Inc located in Princeton, N.J., U.S.A.); cis-3-hexenyl acetate sold under the tradename Verdural extra (available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A.); 2,6-dimethyl-7-octen-2-ol sold under the tradename Dihydromyrcenol (available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A.); para-tertiary-amyl cyclohexanone sold under the tradename Orivone (available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A.); n-decyl aldehyde sold under the tradename Decyl Aldehyde (available from Aceto, Corp. located in Lake Success, N.Y., U.S.A.); and mixtures thereof.
Nonlimiting examples of suitable highly volatile perfumes and their respective boiling point values at 1 atmosphere of pressure are given in U.S. Pat. No. 5,919,440.
Ionone
The odor masking base preferably comprises an ionone perfume component (i.e. an ionone or mixture of ionones) at concentrations ranging from about 15% to about 80%, preferably from about 16% to about 60%, more preferably from about 16% to about 40%, by weight of the odor masking base. Ionones are a well known class of perfume chemicals derived from natural oils or manufactured synthetically, which are typically colorless or pale yellow liquids exhibiting woody violet-like odors.
The ionone perfume for use in the odor masking base has a boiling point at 1 atmosphere of pressure of more than about 250xc2x0 C., preferably more than about 255xc2x0 C., even more preferably more than about 260xc2x0 C., wherein the ionone perfume is preferably selected from methyl ionones, alpha ionones, beta ionones, gamma ionones, or combinations thereof. Nonlimiting examples of suitable ionones include 1-(2,6,6-Trimethyl-2-cyclohexene-1-yl)-1,6-heptadien-3-one, 2-Allyl-para-menthene-(4(8))-ono-3, Pseudo-allyl-alpha-ionone, alpha-Citrylidene cyclopentanone, 5-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-4-methyl-4-penten-3-one, 6-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-1-methyl-5-hexen-4-one, 2,6,6-Trimethyl cyclohexyl-1-butenone-3, Dihydro-alpha-ionone, 4-(2,6,6-Trimethylcyclohexen-1-yl)-butan-2-one, 4-(2-Methylene-6,6-dimethylcyclohexyl)-butan-2-one, 1-(2,5,6,6-Tetramethyl-2-cyclohexenyl)-butan-3-one, Dihydro-beta-irone, Dihydro-gamma-irone, 5-(2,6,6-Trimethyl-2-cyclohexenyl)-pentan-3-one, Dihydro-iso-methyl-beta-ionone, 6-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-5-hexen-4-one, alpha-Ethyl-2,2,6-trimethyl cyclohexane butyric aldehyde, 4-Methyl-6-(1,1,3-trimethyl-2xe2x80x2-cyclohexen-2xe2x80x2-yl)-3,5-hexadien-2-one, 6,10-Dimethyl undecan-2-one, 6-(2,6,6-Trimethyl-1-cyclohexen-1-yl)-1-methyl-2,5-hexadien-4-one, 6-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-1-methyl-2,5-hexadien-4-one, 4-(2,2,6-Trimethyl-2-cyclohexen-1-yl)-3-buten-2-one, 4-(2,6,6-Trimethyl-1-cyclohexen-1-yl)-3-buten-2-one, 4-(2-Methylene-6,6-dimethylcyclohexyl)-3-buten-2-one, Epoxy-2,3-beta-ionone, Ethyl-2,3-epoxy-3-methyl-5-(2,6,6-trimethyl-2-cyclohexenyl)-4-pentenoate, alpha-ionone methylanthranilate, Methyl-2,3-epoxy-3-methyl-5-(2,6,6-trimethyl-2-cyclohexenyl)-4-pentenoate, 4-(2,5,6,6-Tetramethyl-2-cyclohexen-1-yl)-3-buten-2-one, 6-Methyl-beta-ionone, 6-Methyl-gamma-ionone, 4-(2,6,6-Trimethyl-2-cyclohexenyl)-2,3-dimethyl-2-buten-1-al, 4-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-3-methyl-3-buten-2-one, 5-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-4-penten-3-one, 5-(2,6,6-Trimethyl-1-cyclohexen-1-yl)-4-penten 3-one, 4-(2,6,6-Trimethyl-3-cyclohexen-1-yl)-3-methyl-3-buten-2-one, 5-(2-Methylene-6,6-dimethylcyclohexyl)-4-penten-3-one, 4-(2-Methylene-6,6-dimethylcyclohexyl)-3-methyl-3-buten-2-one, 4-(2,3,6,6-Tetramethyl-2-cyclohexen-1-yl)-3-buten-2-one, 4-(2,4,6,6-Tetramethyl-2-cyclohexen-1-yl)-3-buten-2-one, 4-(2,4,6,6-Tetramethyl-1-cyclohexen-1-yl)-3-buten-2-one, 5-Methyl-1-(3-methyl-3-cyclohexenyl)-1,3-hexanedione, 2-Methyl-4-(2,6,6-trimethyl-2-cyclohexenyl)-3-buten-1-al, 3-Methyl-4-(2,4,6-trimethyl-3-cyclohexenyl)-3-buten-2-one, 4-(2-Methyl-5-iso-propenyl-1-cyclopenten-1-yl)-2-butanone, 4-(2,6,6-Trimethyl-7-cycloheptenyl)-3-buten-2-one, 4-(2,6,6-Trimethyl-4-cyclohexenyl)-3-buten-2-one, 2,6-Dimethylundeca-2,6,8-trien-10-one, 2,6,12-Trimethyl-trideca-2,6,8-trien-10-one, 2,6-Dimethyldodeca-2,6,8-trien-10-one, 2,6,9-Trimethylundeca-2,6,8-trien-10-one, 4-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-3-methyl-3-buten-2-one, 4-(2,4,6-Trimethyl-3-cyclohexen-1-yl)-3-buten-2-one, 5-(2-Methylene-6,6-dimethylcyclohexy)-4-penten-3-one, and mixtures thereof.
Preferred ionones include 4-(2,6,6-Trimethyl-3-cyclohexen-1-yl)-3-methyl-3-buten-2-one sold under the tradename Isoraldeine (available from Givaudan Roure, Corp. located in Teaneck, N.J., U.S.A.); 5-(2-Methylene-6,6-dimethylcyclohexyl)-4-penten-3-one sold under the tradename gamma-Methyl Ionone (available from Givaudan Roure, Corp. located in Teaneck, N.J., U.S.A.); 4-(2,2,6-Trimethyl-2-cyclohexen-1-yl)-3-buten-2-one sold under the tradename alpha-Ionone (available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A); 4-(2,6,6-Trimethyl-1-cyclohexen-1-yl)-3-buten-2-one sold under the tradename beta-Ionone (available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A); 4-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-3-methyl-3-buten-2-one sold under the tradename Methyl Ionone (available from Bush Boake Allen, Inc. located in Montvale, N.J., U.S.A.); and mixtures thereof.
Ionones may be incorporated into the odor masking base as one or more individual perfume chemicals or as a specialty perfume containing a combination of perfume chemicals including ionone perfume chemicals. Nonlimiting examples of ionone specialty perfumes include Alvanone Extra available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A., Irisia Base available from Firmenich, Inc located in Princeton, N.J., U.S.A., Irival available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A., Iritone available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A., and mixtures thereof.
Other suitable ionones containing materials for use herein are natural materials such as mimosa, violet, iris, orris and mixtures thereof.
The musk and highly volatile perfumes for use in the odor masking base can also be incorporated into the base as one or more individual perfume chemicals, or as a specialty perfume containing a combination of perfume chemicals. A nonlimiting example of a preferred highly volatile specialty perfume include Cassis Base 345-B available from Firmenich, Inc. located in Princeton, N.J., U.S.A. Nonlimiting examples of suitable ionone perfumes and their respective boiling point values at 1 atmosphere of pressure are given in U.S. Pat. No. 5,919,440.
Musk
The odor masking base preferably comprises a musk component at concentrations of from about 5% to about 70%, preferably from about 15% to about 50%, more preferably from about 20% to about 35%, by weight of the odor masking base. Musk is a well known class of perfumes chemicals that is typically in the form of a colorless or light yellow material having a distinctive, musk-like odor.
The musk component for use in the odor masking base must have a boiling point at 1 atmosphere of pressure of more than about 250xc2x0 C., preferably more than about 255xc2x0 C., even more preferably more than about 260xc2x0 C., wherein the musk component is preferably a polycyclic musk, macrocyclic musk, nitrocyclic musk, or combination thereof, each preferred musk component having more than about 12 carbon atoms, preferably more than about 13 carbon atoms, more preferably more than about 15 carbon atoms.
Suitable polycyclic musks include 5-Acetyl-1,1,2,3,3,6-hexamethylindan, 4-Acetyl-1,1-dimethyl-6-tertiary-butylindan, 7-Acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene, 1,1,4,4-Tetramethyl-6-ethyl-7-acetyl-1,2,3,4-tetrahydronaphthalene, 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-gamma-2-benzopyran, and mixtures thereof.
Suitable macrocyclic musks include cyclopentadecanolide, cyclopentadecanolone, cyclopentadecanone, 3-Methyl-1-cyclopentadecanone, cycloheptadecen-9-one-1, cycloheptadecanone, cyclohexadecen-7-olide, cyclohexadecen-9-olide, cyclohexadecanolide, ethylene tridecane dioate, 10-oxahexadecanolide, 11-oxahexadecanolide, 12-oxahexadecanolide, and mixtures thereof.
Suitable nitrocyclic musks include 1,1,3,3,5-Pentamethyl-4,6-dinitroindan, 2,6-Dinitro-3-methoxy-1-methyl-4-tertiary-butylbenzene, 2,6-Dimethyl-3,5-dinitro-4-tertiary-butyl-acetophenone, 2,6-Dinitro-3,4,5-trimethyl-tertiary-butyl-benzene, 2,4,6-Triinitro-1,3-dimethyl-5-tertiary-butylbenzene, and mixtures thereof.
Preferred musks include 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-gamma-2-benzopyran sold under the tradename Galaxolide (available from International Flavors and Fragrances, Inc. located in New York, N.Y., U.S.A.); cyclopentadecanolide sold under the tradename Exaltolide (available from Firmenich, Inc. located in Princeton, N.J., U.S.A.); ethylene tridecane dioate sold under the tradename Ethylene Brassylate (available from Fragrance Resource, Inc. located, in Keyport, N.J., U.S.A.); 7-Acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene sold under the tradename Tonalid (available from Givaudan Roure, Corp. located in Teaneck, N.J., U.S.A.); and mixtures thereof. Nonlimiting examples of suitable musks and their respective boiling point values at 1 atmosphere of pressure are given in U.S. Pat. No. 5,919,440.
Blooming Perfume
In a preferred embodiment the composition of the invention further comprises a blooming perfume composition. A blooming perfume composition is one which comprises blooming perfume ingredients. A blooming perfume ingredient may be characterized by its boiling point and its octanol/water partition coefficient (P). Boiling point according to the present invention is measured under normal standard pressure of 760 mmHg. The boiling points of many perfume ingredients, at standard 760 mm Hg are given in, e.g., xe2x80x9cPerfume and Flavor Chemicals (Aroma Chemicals),xe2x80x9d Steffen Arctander, published by the author, 1969.
Surfactants
In compositions and methods of the present invention for use in automatic dishwashing the detergent surfactant is preferably low foaming by itself or in combination with other components (i.e. suds suppressers). In compositions and methods of the present invention for use in hard surface cleaning or pretreatment prior to dishwashing, the detergent surfactant is preferably foamable in direct application but low foaming in automatic dishwashing use.
The addition of low level of surfactant selected from anionic, amphoteric, zwitterionic, nonionic and semi-polar surfactants and mixtures thereof, to the composition of the invention aids the cleaning process and also helps to care for the skin of the user. Preferably the level of surfactant is from about 0.05 to about 10%, more preferably from about 0.09 to about 5% and more preferably from 0.1 to 2%. A preferred surfactant for use herein is an amine oxide surfactant.
Surfactants suitable herein include anionic surfactants such as alkyl sulfates, alkyl ether sulfates, alkyl benzene sulfonates, alkyl glyceryl sulfonates, alkyl and alkenyl sulphonates, alkyl ethoxy carboxylates, N-acyl sarcosinates, N-acyl taurates and alkyl succinates and sulfosuccinates, wherein the alkyl, alkenyl or acyl moiety is C5-C20, preferably C10-C18 linear or branched; cationic surfactants such as chlorine esters (U.S. Pat. No. 4,228,042, U.S. Pat. No. 4,239,660 and U.S. Pat. No. 4,260,529) and mono C6-C16 N-alkyl or alkenyl ammonium surfactants wherein the remaining N positions are substituted by methyl, hydroxyethyl or hydroxypropyl groups; low and high cloud point nonionic surfactants and mixtures thereof including nonionic alkoxylated surfactants (especially ethoxylates derived from C6-C18 primary alcohols), ethoxylated-propoxylated alcohols (e.g., Olin Corporation""s Poly-Tergent(copyright) SLF18), epoxy-capped poly(oxyalkylated) alcohols (e.g., Olin Corporation""s Poly-Tergent(copyright) SLF 18Bxe2x80x94see WO-A-94/22800), ether-capped poly(oxyalkylated) alcohol surfactants, and block polyoxyethylene-polyoxypropylene polymeric compounds such as PLURONIC(copyright), REVERSED PLURONIC(copyright), and TETRONIC(copyright) by the BASF-Wyandotte Corp., Wyandotte, Mich.; amphoteric surfactants such as the C12-C20 alkyl amine oxides (preferred amine oxides for use herein include lauryldimethyl amine oxide and hexadecyl dimethyl amine oxide), and alkyl amphocarboxylic surfactants such as Miranol(trademark) C2M; and zwitterionic surfactants such as the betaines and sultaines; and mixtures thereof. Surfactants suitable herein are disclosed, for example, in U.S. Pat. Nos. 3,929,678, 4,259,217, EP-A-0414 549, WO-A-93/08876 and WO-A-93/08874. Surfactants are typically present at a level of from about 0.2% to about 30% by weight, more preferably from about 0.5% to about 10% by weight, most preferably from about 1% to about 5% by weight of composition. Preferred surfactant for use herein are low foaming and include low cloud point nonionic surfactants and mixtures of higher foaming surfactants with low cloud point nonionic surfactants which act as suds suppresser therefor.
Builder
Builders suitable for use in cleaning compositions herein include water-soluble builders such as citrates, carbonates and polyphosphates e.g. sodium tripolyphosphate and sodium tripolyphosphate hexahydrate, potassium tripolyphosphate and mixed sodium and potassium tripolyphosphate salts; and partially water-soluble or insoluble builders such as crystalline layered silicates (EP-A-0164514 and EP-A-0293640) and aluminosilicates inclusive of Zeolites A, B, P, X, HS and MAP. The builder is typically present at a level of from about 1% to about 80% by weight, preferably from about 10% to about 70% by weight, most preferably from about 20% to about 60% by weight of composition.
Preferably compositions for use herein comprise silicate in order to prevent damage to aluminium and some painted surfaces. Amorphous sodium silicates having an SiO2:Na2O ratio of from 1.8 to 3.0, preferably from 1.8 to 2.4, most preferably 2.0 can also be used herein although highly preferred from the viewpoint of long term storage stability are compositions containing less than about 22%, preferably less than about 15% total (amorphous and crystalline) silicate.
Enzyme
Enzymes suitable herein include bacterial and fungal cellulases such as Carezyme and Celluzyme (Novo Nordisk A/S); peroxidases; lipases such as Amano-P (Amano Pharmaceutical Co.), M1 LipaseR and LipomaxR (Gist-Brocades) and LipolaseR and Lipolase UltraR (Novo); cutinases; proteases such as EsperaseR, AlcalaseR, DurazymR and SavinaseR (Novo) and MaxataseR, MaxacalR, ProperaseR and MaxapemR (Gist-Brocades); and xcex1 and xcex2 amylases such as Purafect Ox AmR (Genencor) and TermamylR, BanR, FungamylR, DuramylR, and NatalaseR (Novo); and mixtures thereof. Enzymes are preferably added herein as prills, granulates, or cogranulates at levels typically in the range from about 0.0001% to about 2% pure enzyme by weight of composition.
Bleaching Agent
Bleaching agents suitable herein include chlorine and oxygen bleaches, especially inorganic perhydrate salts such as sodium perborate mono-and tetrahydrates and sodium percarbonate optionally coated to provide controlled rate of release (see, for example, GB-A-1466799 on sulfate/carbonate coatings), preformed organic peroxyacids and mixtures thereof with organic peroxyacid bleach precursors and/or transition metal-containing bleach catalysts (especially manganese or cobalt). Inorganic perhydrate salts are typically incorporated at levels in the range from about 1% to about 40% by weight, preferably from about 2% to about 30% by weight and more preferably from abut 5% to about 25% by weight of composition. Peroxyacid bleach precursors preferred for use herein include precursors of perbenzoic acid and substituted perbenzoic acid; cationic peroxyacid precursors; peracetic acid precursors such as TAED, sodium acetoxybenzene sulfonate and pentaacetylglucose; pernonanoic acid precursors such as sodium 3,5,5-trimethylhexanoyloxybenzene sulfonate (iso-NOBS) and sodium nonanoyloxybenzene sulfonate (NOBS); amide substituted alkyl peroxyacid precursors (EP-A-0170386); and benzoxazin peroxyacid precursors (EP-A-0332294 and EP-A-0482807). Bleach precursors are typically incorporated at levels in the range from about 0.5% to about 25%, preferably from about 1% to about 10% by weight of composition while the preformed organic peroxyacids themselves are typically incorporated at levels in the range from 0.5% to 25% by weight, more preferably from 1% to 10% by weight of composition. Bleach catalysts preferred for use herein include the manganese triazacyclononane and related complexes (U.S. Pat. Nos. 4,246,612, 5,227,084); Co, Cu, Mn and Fe bispyridylamine and related complexes (U.S. Pat. No. 5,114,611); and pentamine acetate cobalt(III) and related complexes(U.S. Pat. No. 4,810,410).
Low Cloud Point Non-ionic Surfactants and Suds Suppressers
The suds suppressers suitable for use herein include nonionic surfactants having a low cloud point. xe2x80x9cCloud pointxe2x80x9d, as used herein, is a well known property of nonionic surfactants which is the result of the surfactant becoming less soluble with increasing temperature, the temperature at which the appearance of a second phase is observable is referred to as the xe2x80x9ccloud pointxe2x80x9d (See Kirk Othmer, pp. 360-362). As used herein, a xe2x80x9clow cloud pointxe2x80x9d nonionic surfactant is defined as a nonionic surfactant system ingredient having a cloud point of less than 30xc2x0 C., preferably less than about 20xc2x0 C., and even more preferably less than about 10xc2x0 C., and most preferably less than about 7.5xc2x0 C. Typical low cloud point nonionic surfactants include nonionic alkoxylated surfactants, especially ethoxylates derived from primary alcohol, and polyoxypropylene/polyoxyethylene/polyoxypropylene (PO/EO/PO) reverse block polymers. Also, such low cloud point nonionic surfactants include, for example, ethoxylated-propoxylated alcohol (e.g., Olin Corporation""s Poly-Tergent(copyright) SLF 18) and epoxy-capped poly(oxyalkylated) alcohols (e.g., Olin Corporation""s Poly-Tergent(copyright) SLF18B series of nonionics, as described, for example, in U.S. Pat. No. 5,576,281).
Preferred low cloud point surfactants are the ether-capped poly(oxyalkylated) suds suppresser having the formula: 
wherein R1 is a linear, alkyl hydrocarbon having an average of from about 7 to about 12 carbon atoms, R2 is a linear, alkyl hydrocarbon of about 1 to about 4 carbon atoms, R3 is a linear, alkyl hydrocarbon of about 1 to about 4 carbon atoms, x is an integer of about 1 to about 6, y is an integer of about 4 to about 15, and z is an integer of about 4 to about 25.
Other low cloud point nonionic surfactants are the ether-capped poly(oxyalkylated) having the formula:
RIO(RIIO)nCH(CH3)ORIII
wherein, RI is selected from the group consisting of linear or branched, saturated or unsaturated, substituted or unsubstituted, aliphatic or aromatic hydrocarbon radicals having from about 7 to about 12 carbon atoms; RII may be the same or different, and is independently selected from the group consisting of branched or linear C2 to C7 alkylene in any given molecule; n is a number from 1 to about 30; and RIII is selected from the group consisting of:
(i) a 4 to 8 membered substituted, or unsubstituted heterocyclic ring containing from 1 to 3 hetero atoms; and
(ii) linear or branched, saturated or unsaturated, substituted or unsubstituted, cyclic or acyclic, aliphatic or aromatic hydrocarbon radicals having from about 1 to about 30 carbon atoms;
(b) provided that when R2 is (ii) then either: (A) at least one of R1 is other than C2 to C3 alkylene; or (B) R2 has from 6 to 30 carbon atoms, and with the further proviso that when R2 has from 8 to 18 carbon atoms, R is other than C1 to C5 alkyl.
Other suitable components herein include organic polymers having dispersant, anti-redeposition, soil release or other detergency properties invention in levels of from about 0.1% to about 30%, preferably from about 0.5% to about 15%, most preferably from about 1% to about 10% by weight of composition. Preferred anti-redeposition polymers herein include acrylic acid containing polymers such as Sokalan PA30, PA20, PA15, PA10 and Sokalan CP10 (BASF GmbH), Acusol 45N, 480N, 460N (Rohm and Haas), acrylic acid/maleic acid copolymers such as Sokalan CP5 and acrylic/methacrylic copolymers. Preferred soil release polymers herein include alkyl and hydroxyalkyl celluloses (U.S. Pat. No. 4,000,093), polyoxyethylenes, polyoxypropylenes and copolymers thereof, and nonionic and anionic polymers based on terephthalate esters of ethylene glycol, propylene glycol and mixtures thereof.
Heavy metal sequestrants and crystal growth inhibitors are suitable for use herein in levels generally from about 0.005% to about 20%, preferably from about 0.1% to about 10%, more preferably from about 0.25% to about 7.5% and most preferably from about 0.5% to about 5% by weight of composition, for example diethylenetriamine penta (methylene phosphonate), ethylenediamine tetra(methylene phosphonate) hexamethylenediamine tetra(methylene phosphonate), ethylene diphosphonate, hydroxy-ethylene-1,1-diphosphonate, nitrilotriacetate, ethylenediaminotetracetate, ethylenediamine-N,Nxe2x80x2-disuccinate in their salt and free acid forms.
The compositions herein can contain a corrosion inhibitor such as organic silver coating agents in levels of from about 0.05% to about 10%, preferably from about 0.1% to about 5% by weight of composition (especially paraffins such as Winog 70 sold by Wintershall, Salzbergen, Germany), nitrogen-containing corrosion inhibitor compounds (for example benzotriazole and benzimadazolexe2x80x94see GB-A-1137741) and Mn(II) compounds, particularly Mn(II) salts of organic ligands in levels of from about 0.005% to about 5%, preferably from about 0.01% to about 1%, more preferably from about 0.02% to about 0.4% by weight of the composition.
Other suitable components herein include colorants, water-soluble bismuth compounds such as bismuth acetate and bismuth citrate at levels of from about 0.01% to about 5%, enzyme stabilizers such as calcium ion, boric acid, propylene glycol and chlorine bleach scavengers at levels of from about 0.01% to about 6%, lime soap dispersants (see WO-A-93/08877), suds suppressors (see WO-93/08876 and EP-A-0705324), polymeric dye transfer inhibiting agents, optical brighteners, perfumes, fillers and clay.
Liquid detergent compositions can contain water and other volatile solvents as carriers. Low quantities of low molecular weight primary or secondary alcohols such as methanol, ethanol, propanol and isopropanol can be used in the liquid detergent of the present invention. Other suitable carrier solvents used in low quantities includes glycerol, propylene glycol, ethylene glycol, 1,2-propanediol, sorbitol and mixtures thereof.
Process of Cleaning Dishware
The compositions of the present invention are especially useful in direct application for pre-treatment of cookware or tableware soiled with cooked-, baked- or burnt-on residues (or any other highly dehydrated soils). The compositions are applied to the soiled substrates in the form for example of a spray or foam prior to automatic dishwashing, manual dishwashing, rinsing or wiping. The pre-treated cookware or tableware can feel very slippery and as a consequence difficult to handle during and after the rinsing process. This can be overcome using divalent cations such as magnesium and calcium salts, especially suitable for use herein is magnesium chloride. The addition of from about 0.01% to about 5%, preferably from about 0.1% to about 3% and more preferably from about 0.4% to about 2% (by weight) of magnesium salts eliminates the slippery properties of the cookware or tableware surface without negatively impacting the stability of physical properties of the pre-treatment composition. The compositions of the invention can also be used as automatic dishwashing detergent compositions or as a component thereof.
In a method aspect, the invention provides a method of removing cooked-, baked- or burnt-on soils from cookware and tableware comprising treating the cookware/tableware with the hard surface cleaning composition of the invention. There is also provided a method of removing cooked-, baked- or burnt-on polymerised grease soils or carbohydrate soils from metallic cookware and tableware comprising treating the cookware/tableware with the hard surface cleaning of the present invention. Preferred methods comprise the step of pre-treating the cookware/tableware with the composition of the invention prior to manual or automatic dishwashing. If desired the process of removing of cooked-, burnt- and baked-on soils can be facilitated if the soiled substrate is covered with cling film after the cleaning composition of the invention has been applied in order to allow swelling of the soil to take place. Preferably, the cling film is left in place for a period of about 1 hour or more, preferably for about 6 hours or more.
There is also provided a hard surface cleaning product comprising the hard surface cleaning composition of the invention and a spray dispenser. The physical properties of the composition and the geometrical characteristic of the spray dispenser in combination are such as to provide spray droplets with an average equivalent geometric diameter from about 3 xcexcm to about 10 xcexcm, preferably from about 4 xcexcm to about 7 xcexcm, as measured using a TSI Aerosizer, such droplet size range being optimum from the viewpoint of odor impression and reduced malodor characteristics. Suitable spray dispensers include hand pump (sometimes referred to as xe2x80x9ctriggerxe2x80x9d) devices, pressurized can devices, electrostatic spray devices, etc.
The present invention envisages spray-type hard surface cleaning compositions for the pre-treatment of cookware and tableware soiled with cooked-, baked- or burnt-on soils in order to facilitate the subsequent cleaning process. The compositions are characterised by having an organic solvent system, including at least one solvent component acting as soil swelling agent, as well as having a pleasant smell. This smell is mainly achieved by the use of an odor-masking perfume or by the combination of an odor masking perfume and a blooming perfume composition. The invention also envisages methods for the removal of the soils mentioned above.